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 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
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 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
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 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is mozilla.org code.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1998
 * the Initial Developer. All Rights Reserved.
 *
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 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
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package com.github.jspxnet.io.chardet;

import java.lang.*;

public class nsEUCSampler {

    int mTotal = 0;
    int mThreshold = 200;
    int mState = 0;
    public int[] mFirstByteCnt = new int[94];
    public int[] mSecondByteCnt = new int[94];
    public float[] mFirstByteFreq = new float[94];
    public float[] mSecondByteFreq = new float[94];

    public nsEUCSampler() {
        Reset();
    }

    public void Reset() {
        mTotal = 0;
        mState = 0;
        for (int i = 0; i < 94; i++) {
            mFirstByteCnt[i] = mSecondByteCnt[i] = 0;
        }
    }

    boolean EnoughData() {
        return mTotal > mThreshold;
    }

    boolean GetSomeData() {
        return mTotal > 1;
    }

    boolean Sample(byte[] aIn, int aLen) {

        if (mState == 1) {
            return false;
        }

        int p = 0;

        // if(aLen + mTotal > 0x80000000)
        //    aLen = 0x80000000 - mTotal;

        int i;
        for (i = 0; (i < aLen) && (1 != mState); i++, p++) {
            switch (mState) {
                case 0:
                    if ((aIn[p] & 0x0080) != 0) {
                        if ((0xff == (0xff & aIn[p])) || (0xa1 > (0xff & aIn[p]))) {
                            mState = 1;
                        } else {
                            mTotal++;
                            mFirstByteCnt[(0xff & aIn[p]) - 0xa1]++;
                            mState = 2;
                        }
                    }
                    break;
                case 1:
                    break;
                case 2:
                    if ((aIn[p] & 0x0080) != 0) {
                        if ((0xff == (0xff & aIn[p]))
                                || (0xa1 > (0xff & aIn[p]))) {
                            mState = 1;
                        } else {
                            mTotal++;
                            mSecondByteCnt[(0xff & aIn[p]) - 0xa1]++;
                            mState = 0;
                        }
                    } else {
                        mState = 1;
                    }
                    break;
                default:
                    mState = 1;
            }
        }
        return (1 != mState);
    }


    void CalFreq() {
        for (int i = 0; i < 94; i++) {
            mFirstByteFreq[i] = (float) mFirstByteCnt[i] / (float) mTotal;
            mSecondByteFreq[i] = (float) mSecondByteCnt[i] / (float) mTotal;
        }
    }

    float GetScore(float[] aFirstByteFreq, float aFirstByteWeight,
                   float[] aSecondByteFreq, float aSecondByteWeight) {
        return aFirstByteWeight * GetScore(aFirstByteFreq, mFirstByteFreq) +
                aSecondByteWeight * GetScore(aSecondByteFreq, mSecondByteFreq);
    }

    float GetScore(float[] array1, float[] array2) {
        float s;
        float sum = 0.0f;

        for (int i = 0; i < 94; i++) {
            s = array1[i] - array2[i];
            sum += s * s;
        }
        return (float) java.lang.Math.sqrt(sum) / 94.0f;
    }
}


